/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.visitor;

import proguard.classfile.*;
import proguard.classfile.util.ClassUtil;

/**
 * This MemberVisitor delegates its visits to one of two other given MemberVisitor instances, depending on whether the
 * visited method is a static initializer or instance initializer, or not.
 *
 * @author Eric Lafortune
 */
public class InitializerMethodFilter implements MemberVisitor {
    private final MemberVisitor initializerMemberVisitor;
    private final MemberVisitor otherMemberVisitor;

    /**
     * Creates a new InitializerMethodFilter.
     * 
     * @param initializerMemberVisitor the member visitor to which visits to initializers will be delegated.
     */
    public InitializerMethodFilter(MemberVisitor initializerMemberVisitor) {
        this(initializerMemberVisitor, null);
    }

    /**
     * Creates a new InitializerMethodFilter.
     * 
     * @param initializerMemberVisitor the member visitor to which visits to initializers will be delegated.
     * @param otherMemberVisitor the member visitor to which visits to non-initializer methods will be delegated.
     */
    public InitializerMethodFilter(MemberVisitor initializerMemberVisitor, MemberVisitor otherMemberVisitor) {
        this.initializerMemberVisitor = initializerMemberVisitor;
        this.otherMemberVisitor = otherMemberVisitor;
    }

    // Implementations for MemberVisitor.

    public void visitProgramField(ProgramClass programClass, ProgramField programField) {}

    public void visitLibraryField(LibraryClass libraryClass, LibraryField libraryField) {}

    public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod) {
        MemberVisitor memberVisitor = applicableMemberVisitor(programClass, programMethod);

        if (memberVisitor != null) {
            memberVisitor.visitProgramMethod(programClass, programMethod);
        }
    }

    public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod) {
        MemberVisitor memberVisitor = applicableMemberVisitor(libraryClass, libraryMethod);

        if (memberVisitor != null) {
            memberVisitor.visitLibraryMethod(libraryClass, libraryMethod);
        }
    }

    // Small utility methods.

    /**
     * Returns the appropriate member visitor, depending on whether the given method is an initializer or not.
     */
    private MemberVisitor applicableMemberVisitor(Clazz clazz, Member method) {
        return ClassUtil.isInitializer(method.getName(clazz)) ? initializerMemberVisitor : otherMemberVisitor;
    }
}
